panasonic txp 42ut30b runs hot

[jimbofz]

Hi just given this plasma to save from landfill
and no suprise y sus igbts s/c
the originals 30f131 x4
i used rjp63k2 as i had these in stock ,
(and theres so many fake 30f131s around)

two diodes d401 rf1501 and
d421 rfn10ns3s were both s/c
so i used two rf2001 n3d again as i had these in stock
after checking buffers etc i tried it on and it works fine .
after 2 hours i checked it and the igbts seem to be running very hot
you wouldnt want to keep your finger on them for more than a few seconds.

i know on plasmas that the igbts do run hot ,
this is why the early ones had fans fitted ,
and on some they are bolted to a large heatsink
but im wondering if they would run cooler with alternative igbt equivalents ?
the y sus is type TNPA 5349
i would value your opinion ,perhaps they run hot anyway
i may experiment with a small 12v fan to see if it cools the board

[ReeceyBurger123]

Re: panasonic txp 42ut30b runs hot

Checked their respective resistors for open circuit or high resistance ? I’ve had them fail, they run hot though I add heat sinks when and where I can to them sets too.

[jimbofz]

Re: panasonic txp 42ut30b runs hot

Checked their respective resistors for open circuit or high resistance ? I’ve had them fail, they run hot though I add heat sinks when and where I can to them sets too.

thanks
i checked all the gate resistors
and resoldered them as the board did look a bit discoloured.
ive added a simple 12v fan fed from 15v supply via 100 ohm resistor(runs at 11.5v)
theres enough room to fit when rear cover is fitted ,
it runs quiet and now the igbts are running so much cooler,
just curious why pana use two different diodes when the data sheets for these seem the same?
d401=rf1501
d421 =rfn10n53s
i replaced both with rf2001 n3d
ill report back after long soak test
the picture quality is superb

[jimbofz]

Re: panasonic txp 42ut30b runs hot

just an update
after running all day for 4 days with back cover on ,
all good ,runs nice and cool .
so anyone repairing one of these dont hesitate to use RJP63K2 igbts as they work a treat.

[R_J]

Re: panasonic txp 42ut30b runs hot

just curious why pana use two different diodes when the data sheets for these seem the same?

The RFN10NS3S is a 10 amp, The RF1501NS3S is a 20 amp

[jimbofz]

Re: panasonic txp 42ut30b runs hot

The RFN10NS3S is a 10 amp, The RF1501NS3S is a 20 amp

thanks RJ
the RF2001 n3d is rated as 20amp
so they should be up to spec as good replacements